Compared to their metallic cousins, fiber optic cables are light in weight. For example, a cable comprised of twisted pairs of insulated copper conductors capable of carrying a given traffic load weights many times that of a fiber optic cable having the same traffic capacity. In some instances, fiber optic cables designed for underwater duty are so light in weight that they would actually float on water absent an added weight, i.e., a heavy and expensive messenger. Such cable construction is expensive and unnecessary and it is to the solution of this prior art problem that the present invention is addressed.